Low-level activity measurements by simultaneous beta counting in anticoincidence and difference

The variable background is an important disturbing factor for low-level activity measurements by beta counting. In order to overcome this difficulty in a simple manner a software-aided technique of simultaneous counting in anticoincidence and difference modes has been established. The technique is based on a programmable multi-channel scaler provided with appropriate software for data analysis. Using this counting system, the technique has been tested by performing low-level activity measurements both in a stable and a time-dependent background.